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61.
应用活化鲁米诺,用优化的增强化学发光酶联免疫分析体系测定人绒毛膜促性腺激素,检测限为0.2mIU/ml。线性范围0~200mIU/ml,与放射免分析测定结果比较,相关性良好。进而又发展了一种半定量的照相测定法,通过实际血清样品测定,效果良好。 相似文献
62.
Pan Ziqiang Fan Shengen Cong Huiling 《Journal of Radioanalytical and Nuclear Chemistry》1996,206(2):239-249
The exposure dose status on radioisotope production and application in China has been assessed in the paper. The average annual occupational exposure dose received by workers in the radioisotope production is about one tenth of the annual dose limit in normal situation. It is less than one twentieth for workers in the radioisotope applications. However, the annual collective dose for the latter is higher than the former by one oder of magnitude due to the larger number of workers in the application field. Although the output of radioisotopes increased doubly in 1980's as compared with 1970's, the increase on the annual collective dose was not obvious. For exposure to the public,131I for example, the collective dose in the radioisotope production decreased by one to two orders of magnitude and the releasing factor reduced by two orders of magnitude. Therefore, the exposure dose received by workers in radioisotope production and application is lower in normal situation. However, the facts worth paying attention to are that there were many events and accidents which happened in the radioisotope applications, especially at the irradiation facilities. The probability of fatal accident was as high as 10–3 per irradiator year. In order to improve the radiation safety situation, it is imperative to conduct the safety assessment for irradiation facilities, to enhance management of the radioactive wastes and spent sources and to establish the experience feedback system. 相似文献
63.
Wei Wang Rongliang Wang Fan Wu Boshun Wan 《Reaction Kinetics and Catalysis Letters》2005,85(2):277-282
Summary A Ni-promoted ligand free palladium catalyst system for Suzuki coupling of aryl bromides has been developed in high efficiency under mild reaction conditions. It was obtained in situ by introducing NiCl2 to PdCl2/PVP using a parallel high-throughput screening technique. A wide range of aryl bromides bearing a variety of functional groups was evaluated. 相似文献
64.
STUDY ON 1-HEXENE POLYMERIZATION BASED ON ZIEGLER-NATTA CATALYSTS WITH DOPED SUPPORT 总被引:1,自引:0,他引:1
XueJiang Zhi-qiangFan 《高分子科学》2004,(4):305-308
A series of Ti/Mg supported catalysts are prepared by using ball-milled mixtures of MgCl2-ethanol adducts and NaCl as supports, and 1-hexene polymerizations catalyzed by the novel catalysts are studied. It is found that the molecular weight distribution of poly(1-hexene) becomes apparently narrower when catalysts with doped supports are used, indicating that changing the structure of the support is an effective way to regulate the active center distribution of heterogeneous Ziegler-Natta catalyst. 相似文献
65.
Fan CA Hu XD Tu YQ Wang BM Song ZL 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(18):4301-4310
A novel and highly diastereoselective samarium-catalyzed tandem rearrangement/reduction of secondary alpha-hydroxy epoxides, which involves a C1 to C3 carbon migration rearrangement and a very interesting hetero-Tishchenko reduction of the intermediate aldehyde and the reductant aldehyde, has been reported. This reaction could be developed to provide a facile and stereoselective construction of 2-quarternary 1,3-diol units with an hydroxymethyl moiety attached to the diastereogenic quaternary carbon center. Detailed investigations have been carried out concerning the screening of the aldehydes as a reductant, the optimization of reaction conditions, and the substrate scope of this tandem reaction. A catalytic cycle for this reaction, the electronic and steric effects of the reductant aldehydes, and the mechanism for the acyl migration of 1,3-diol monoesters are proposed. 相似文献
66.
Yun‐Yu Liu Guang‐Shan Zhu Guo‐Zhen Fan Shi‐Lun Qiu 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):m159-m160
In the title compound, poly[μ5‐pyrazine‐2,3‐dicarboxylato‐cadmium(II)], [Cd(C6H2N2O4)]n or [Cd(pdc)]n, where pdc is the pyrazine‐2,3‐dicarboxylate anion, the CdII atom is six‐coordinated by five carboxylate O atoms and one N atom from five different pdc ligands in a distorted octahedral CdO5N coordination geometry. Two CdII atoms are bridged by carboxylate groups of the pdc ligands to create a dimeric unit. The dimeric units are further connected by the pdc ligands to generate an interesting two‐dimensional structure. 相似文献
67.
大庆渣油族组分非等温热反应的研究 总被引:2,自引:0,他引:2
采用动态热重分析法在升温速率为6.2K·min ̄(-1)及惰性气流量100cm ̄3·min ̄(-1)的条件下,对大庆渣油族组分的热转化行为进行了考察,获得了族组分的热转化速率峰值、速率峰值处的反应温度、转化率和剧裂分解温度区间等动力学基本数据以及各族组分的生焦性能。数据分析表明,族组分的热反应活性顺序为:饱和分>胶质>芳香分>沥青质。在大庆渣油族组分热转化的两个温区内,采用分段一级动力学模型较好地拟合了实验数据,确定了各族组分在两个温区内的热反应动力学参数。 相似文献
68.
69.
The double-T injector design employed in many microchip capillary electrophoresis devices allows for the formation of very small (50-500 pL) sample plugs for subsequent analysis on-chip. In this study, we show that sample plugs formed at the channel junction can be geometrically defined. The channel width and injector symmetry prove to be of great importance to good performance. A unique pushback of solvent into the side channels can be induced when the side channels have a very low resistance to flow, and this helps to better define the injected sample plug. Samples and running buffers of differing ionic strength (e.g., 10 mM KCl buffer and 20 mM KCl sample) can yield widely variable results in terms of plug shape and amount injected (variations of 1.5 to 10x). Applying bias voltages to all the intersecting channels aids in controlling the plug shape. However, when the ionic strengths of buffer and sample are not matched, the actual amount injected (up to 10x variations) can be inconsistent with the appearance of the plug formed in the injector (up to only 30 % variations). Operating at constant pH and ionic strength produced the most consistent results. This report examines the effects of altering the injector geometry and solution ionic strengths, and presents the results of using bias voltages to control plug formation. The observed results should provide a benchmark for modeling of the fluid dynamics in channel intersections. 相似文献
70.